The present invention relates generally to an improved shopping cart system and more particularly to a shopping cart detection system having a signalling device for signalling the presence of a load on the lower tray or shelf of the shopping cart.
One problem which grocery stores, discount stores, etc. have experienced throughout the years, particularly stores where the customers are allowed to wheel the shopping cart out into the parking lot with the merchandise or groceries he or she has purchased, is the failure to charge the customer for items placed on the lower tray or shelf of the shopping cart. These items are often missed by the checkout clerk since his or her view of the lower tray is often obstructed as the cart is pushed through the checkout aisle. It has been found that even if the checkout clerk is told to specifically check each cart to make sure that there are no items on the lower shelf which have not been accounted for, he or she often forgets to do this, particularly during busy hours. As a result, the shopping cart is pushed through the checkout station and then either wheeled out to the parking lot and unloaded by the customer or by a carry-out person on the assumption that the items have been paid for.
This problem has previously been recognized by others. For example, U.S. Pat. No. 2,918,294 granted to Hennion discloses a shopping cart with means for indicating when the lower tray or basket is loaded with merchandise. This device includes an indicating means connected with the basket portion of the cart and a cable element which is connected with a portion of the cart and is movable between an upper and a lower position in response to a portion of the movement of the lower tray about a forward pivot point. In this device, there is no direct connection between the cable and the lower tray. Rather, these two elements operate independently of one another. Thus, two spring members are necessary: one spring to retain the lower tray in a normally raise position and a second spring to maintain the cable element in a normally raised position. This results in a structure which is quite complicated and is not readily adaptable as a retrofit item.
U.S. Pat. No. 3,051,936 granted to Finger et al. discloses an alarm system for a shopping cart. This alarm indicates the presence of a load on the lower shelf of the cart by completing a circuit when the cart is wheeled through the checkout aisle. This device is also quite complicated structurally and is also not readily adaptable as a retrofit item. Further, it requires the installation of contact strips in the checkout aisles to facilitate completion of the electrical circuit, an installation which is unattractive and also expensive.
Others have also recognized the problem resulting from the failure to account for and charge customers for items placed on the lower shelf of shopping carts, however, the devices described in the prior art have not eliminated the problem. Although these devices may function satisfactorily in certain applications, they appear to have limitations. For example, most are relatively complicated structures which appear to be designed for a special type of shopping cart with limited flexibility for retrofitting on shopping carts already in use. Accordingly, a need continues to exist for a shopping cart with an improved means for signalling the presence of a load on the lower shelf of the cart which is simple in construction, which is unobvious to the customer and which can be easily retrofitted on shopping carts presently in use.